A Nearly Scale Invariant Spectrum of Gravitational Radiation from Global Phase Transitions

Katherine Jones-Smith; Lawrence M. Krauss; Harsh Mathur

doi:10.1103/physrevlett.100.131302

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arXiv · 0712.0778

A Nearly Scale Invariant Spectrum of Gravitational Radiation from Global Phase Transitions

Katherine Jones-Smith·Lawrence M. Krauss·Harsh Mathur

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Abstract

Using a large N sigma model approximation we explicitly calculate the power spectrum of gravitational waves arising from a global phase transition in the early universe and we confirm that it is scale invariant, implying an observation of such a spectrum may not be a unique feature of inflation. Moreover, the predicted amplitude can be over 3 orders of magnitude larger than the naive dimensional estimate, implying that even a transition that occurs after inflation may dominate in Cosmic Microwave Background polarization or other gravity wave signals.

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Katherine Jones-Smith, Lawrence M. Krauss, Harsh Mathur. 2008-06-24. A Nearly Scale Invariant Spectrum of Gravitational Radiation from Global Phase Transitions. https://doi.org/10.1103/physrevlett.100.131302

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